Predefined constants

The following mathematical constants are recognized: pi, tau, and eu, where tau is \(2\pi\) and eu represents Euler's constant \(e\). They are stored as floating-point number literals and can be used in arithmetic expressions with operators, e.g., pi/2 equals \(\tfrac{\pi}{2}\).

The latter can be used, for example, as an argument for a parameterized gate, i.e.,

 Rx(pi/2) q[0]